2009-01-21

As per January 2009, the current stable version of GNU/Emacs is 22. However, there is a development version 23 available from CVS. The development version should become the next stable version in the not-too-distant future. I've been using emacs 23 for more than one year now, and have found it very reliable.

I'll be discussing some of the Emacs 23 specific tricks in some future entries, here I will discuss a small number of visible ones. This does not even scratch the surface of what is new - it's just a little taster.

One of the biggest, user-visible changes in Emacs 23 is the support for anti-aliased fonts on X11. This means that the fonts will look much smoother -- and as noted, users feel more effective when using pretty technology. In this case, some pictures are probably in order; the two screenshots show emacs-22 versus emacs-23, using default settings. The difference is striking, to say the least.

Emacs also supports variable-width fonts, so you could use any TrueType (and some other) font. However, I prefer to use a fixed-width font; a nice one is the Inconsolata font (ttf-inconsolata in Ubuntu/Debian, inconsolata-fonts in Fedora).

Another interesting new feature is DBUS-support; D-Bus is an IPC system used on Linux/Unix to communicate between applications. Using D-Bus, Emacs now even has support for querying the network for ZeroConf-devices when you are using Avahi; for example, insert a list of all printers in the local network into the current buffer, you could do something like:

Of course, this is not so useful. But being able to use Zeroconf (and D-Bus) easily from within emacs enables all kinds of interesting hacks... to be continued.

A maybe-useful graphical gimmick is that you can now change the 'opacity' (non-transparency) of your emacs frame (window) if you're on MS-Windows, or on some X with compositing enabled (Compiz, metacity-with-compositing, ...).

(modify-frame-parameters (selected-frame)
`((alpha . 90)))

will make your frame (window) 90% opaque (ie., 10% transparant).

If you're very conservative, you should of course wait for the official release of the new emacs. If you are a bit more adventurous, I can definitely recommend it. I have not come across any bugs. Of course, your mileage may vary.

I guess there must be similar packages for Fedora/Suse/... but I could only find some older packages from EmacsCvsAndFedora. That says more about my searching skill than anything else, I guess... You can however also compile the new emacs yourself; it's not too difficult and there are some instructions in EmacsWiki, but note that the page is partly outdated.

Final note: if you have to have some emacs-23 specific code in your .emacs, but you also need emacs-22, you can use some like:

@cos: fair point; in this case it's just meant for temporarily trying out some emacs23 things when your still also using an older version. for the longer term, it's indeed better to figure out how to test for specific features.